The invention relates to a vehicle fuel system.
Prior art systems and methods for removing fuel from a plurality of supply tanks often pumped the liquid from one tank and employed interconnecting piping or crossover lines coupled to the bottom walls of the supply tanks to provide flow of fluid between the tanks. These crossover lines were generally the lowest parts on a vehicle since flow between tanks depended upon gravitational forces, and were generally susceptible to accidental rupture since they were exposed to debris, stones, etc., on roads. Their exposed location also increased the susceptibility to rupture in accident situations. This susceptibility to accidental rupture created a generally unsafe condition, especially when the supply tanks were fuel tanks on a truck, tractor or other vehicles.
In an effort to resolve the above problem, some systems required one tank to be emptied and then a valve activated to start using the other fuel tank. Drawbacks to this system were that they involved additional expensive mechanical parts, such as valves, subject to breakdown. Further, prior art systems did not provide or control the feed and return of fuel to equalize the liquid level in the separate supply tanks.